Control of vehicular traffic on roads is important to the proper functioning of society and its economy. To provide such control, traffic light switching systems are employed. One conventional traffic light switching system counts a predetermined number of vehicles entering a road intersection and change the lights accordingly. Some conventional traffic light switching systems, referred to as "loop detectors" include a conductive loop detector embedded in the road. The conductive loop generates an electromagnetic field. A signal is transmitted to a traffic light controller if the proper number of vehicles have passed over the conductive loop and through the electromagnetic field. The traffic light controller then switches the traffic light, if appropriate. In addition to electromagnetic fields, prior systems have also used pressure sensors to determine the presence of a vehicle.
The use of physical loop detectors in conventional traffic light switching systems is primitive and conventionally used only to detect the existence of traffic in a specific direction. A problem with physical loop detectors is that they are permanently embedded in the roadway and cannot be quickly or easily moved or modified. In addition, physical loop detector systems cannot selectively change a traffic light based on the type of vehicle passing over the detector. Current systems also cannot receive information from other sources to determine whether to change the light for a particular vehicle. As a result, conventional traffic light switching systems perform at a lower level than desired.
Other systems have been developed to solve this problem by allowing the drivers of certain vehicles to send a signal to the traffic light controller in order to change the traffic light. However, the problem with such a system is that it cannot prioritize different signals coming from separate vehicles. In addition, the drivers of such vehicles can switch traffic signals in their favor even if it is not essential. This misuse of the system has an adverse effect on other vehicular traffic.